how to get protection if wife files a wrong case

Sir/Madam, We are three brothers staying separately in different towns, parents are staying with my younger brothers. I am staying in different city and my middle brother stays in our native with his wife. His wife goes to her parents house frequently and not allowing my parents to their native for a single day. When they go to our native she leaves the house and makes us phone calls stating that your parents should not come here and if they don't return she will consume poison and we all will be in soup. She is very abusive and talks very roughly. This is her second marriage, earlier also she had fight with her ex husband and the lady has taken some amount from him for getting divorce. She has 18 years old son from his ex-husband and staying with her parents. My self is doing a government job and my both brothers are doing private jobs. I did not keep any relation with the lady and my brother at all as her behaviour is not appropriate. Kindly advise us what should we do so that if she files any wrong case under the woman's right or DVA or any other. what is the option left with us under these circumstances?